Im sorry if this has been posted before. I tried to find a thread for this but came up empty handed. I am setting up a home network from which I plan to run a linux server eventually on a cable modem. I am working on this from the ground up. I am testing different software and different os's to learn their weaknesses and how to protect them. I read that what one really needs, not just a firewall or a virus scanner, is good intrusion detection software. I am wondering if anyone knows of a good one that is free, or any that are for that matter, so that I use them in my testing and learning. I appreciate your help. If there are no free ids's then what are some good ones to purchase? Thanks.